And staying in Washington, now. Today, the gloves were off there, amid allegations of spy games. Senators accusing the cia of spying on their work. Tonight, the justice department is investigating. And ABC's Jeff Zeleny takes us inside the heated battle. Reporter: The cia, portrayed in the movie "Zero dark thirty," trying to squeeze secrets from terror suspects. You give me the information I need. Reporter: But today, the spy agency is accused of spying on the U.S. Senate. Infiltrating computers used by the senate intelligence committee. I have grave concerns that the cia's search may well have violated the separation of powers principles. Reporter: The fireworks stem from a senate investigation into the cia's secret interrogation techniques used after 9/11. Senate staffers were invited into an undisclosed cia office to review thousands of documents. It was there, senator Feinstein says, the cia secretly searched her staff's computers, removing documents. She says nearly 1,000 pages went missing. Cia director John Brennan denied the charges. We wouldn't do that. Reporter: The white house says it's taking the allegations seriously. But has confidence in Brennan. Peter earnest, a cia officer for three decades, says he's never seen such a standoff. I recall nothing like this. Reporter: One senator saying, tonight, this is Nixon stuff. Jeff Zeleny, ABC news, the capitol.

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